1. Field of the Invention
The present invention relates to a multilayer ceramic capacitor and, more particularly, a high capacity multilayer ceramic capacitor having excellent reliability.
2. Description of the Related Art
In general, an electronic component fabricated using a ceramic material, such as a capacitor, an inductor, a piezoelectric device, a varistor, a thermistor, or the like, generally has a ceramic body made of a ceramic material, internal electrodes provided in the ceramic body, and external electrodes (that is, termination electrodes) placed on surfaces of the ceramic body so as to be connected to respective internal electrodes.
Among ceramic electronic components, a multilayer ceramic capacitor has beneficial features such as small size but high capacity, ease of mounting, and the like, and is therefore widely used as a component of mobile communications equipment such as computers, PDAs, mobile phones, and so forth.
In recent years, with the trend towards smaller sized multi-functional electronic products, electronic parts have have tended to have a smaller size and high performance. In response, high capacity multilayer ceramic capacitors having a large capacity while having a small size are required. Accordingly, a multilayer ceramic capacitor, in which thicknesses of dielectric layers and internal electrodes are decreased, such that the dielectric layers and internal electrodes are highly-multilayered, is currently being manufactured.
However, in the case in which voltages per unit thickness are higher with a decrease in a thickness of the dielectric layer, dielectric breakdown may readily occur even when low voltage is applied. In general, when voltage is applied to a multilayer ceramic capacitor, an electric field is concentrated in both ends of the internal electrode rather than the center thereof in a length direction and insulation breakdown may occur at the ends of a multilayer ceramic capacitor if the dielectric layers in the center thereof have no defects.
Specifically, in the case of a rectangular pattern wherein the ends of internal electrodes are formed in parallel to a lamination direction, a lamination distance between the ends is small and an electric field strength is increased, leading to a deterioration in insulation breakdown voltage (BDV) properties.
Meanwhile, an end portion of a withdrawal portion of an internal electrode (‘internal electrode withdrawal portion’) is a portion to which an external electrode is applied at a minimal coating thickness, and thus, may easily be penetrated by a plating solution. If a width of the internal electrode withdrawal portion is large while a width of a margin portion of the dielectric layer is small, the plating solution may penetrate at an interface between the internal electrode and the dielectric layer, which in turn, may cause structural defects such as cracks and ultimately increase the possibility of a deterioration in reliability. Therefore, there are limitations in the development of high capacity multilayer ceramic capacitors and the miniaturization thereof.